Method for activating an electromagnetic valve

Abstract

A method is for activating an electromagnetic valve including a valve seat and a valve body. The valve body is movable between a first and the second position (A, B) via an electric drive coil. The drive coil is connected to a control device which as a function of a setting variable (S) energizes the drive coil with a signal sequence consisting of control signals in order to move the valve body. The control device as a function of the setting variable (S) sets a predetermined signal amplitude and / or a predetermined signal duration of the control signals. It is provided that at least one control signal of the signal sequence is formed with an amplitude superelevated above the predetermined signal amplitude and / or with a signal duration extended beyond the predetermined signal duration.

Description

CROSS REFERENCE TO RELATED APPLICATION[0001]This application claims priority of European patent application no. 17 400 038.0, filed Jun. 9, 2017, the entire content of which is incorporated herein by reference.FIELD OF THE INVENTION[0002]The invention relates to a method for activating an electromagnetic valve including a valve seat and a valve body. The valve body is movable between a first position and a second position, for which purpose an electromechanical drive with an electric drive coil is provided. The electric drive coil is activated by a control device which as a function of a setting variable activates the drive coil of the electromagnetic valve with a signal sequence. The signal sequence output by the control device has a predetermined frequency and / or control signals with a signal amplitude predetermined by the control device and / or a signal duration predetermined by the control device.BACKGROUND OF THE INVENTION[0003]U.S. Pat. No. 7,713,111 discloses a control device ...

AI Technical Summary

Benefits of technology

[0009]The signal sequence consisting of control signals, which is supplied to the electromagnetic valve, is superelevated in the frequency, the signal amplitude and / or the signal duration irrespective of the values predetermined by the control device. This means that at least one control signal of the signal sequence is formed with a signal amplitude superelevated above the predetermined signal amplitude and / or with a signal duration extended beyond the predetermined signal duration and / or with a signal sequence frequency increased over a predetermined frequency. The effect which can thereby be achieved is that the drive coil of the electromagnetic valve is energized with a greater or longer lasting current, as a result of which a greater electromagnetic force is exerted on the valve body. The greater electromagnetic force ensures that the valve body is reliably moved despite jamming or sticking. The functioning capability of the valve is ensured. There is no feedback as to whether the valve body has or has not moved.

[0012]Alternatively or additionally, it can be provided to form the predetermined signal duration of the control signal with a 5% to 50% longer signal duration than the predetermined signal duration. The extended signal duration is expediently 20% longer than the signal duration predetermined by the control device for operation of the valve. As a result, a longer action of the electromagnetic setting force on the valve body can be ensured, which is sufficient in most cases in order initially to move a jammed or stuck valve body.

[0013]If, for example, a first control signal is selected to be significantly greater in its superelevated signal amplitude than the predetermined signal amplitude and, furthermore, the control signal is formed with a longer signal duration than the predetermined signal duration of the control signal, even in stubborn cases an initial release of a jammed or stuck valve body, and therefore the function of the electromagnetic valve, can be ensured.

Problems solved by technology

Irrespective of the use of an electromagnetic valve as a water valve, as a fuel valve or similar valve, the valve body of the valve may stick to the valve seat, may become jammed or may become sluggish in some other way.

If an electromagnetic valve for setting a small volumetric flow is activated with only short operating pulses, a movement of the valve body may fail because of sticking, jamming or a similar obstruction.

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